RWInterval< T > Class Template Reference
[Model Selection]

A class template for describing an interval of values. More...

#include <rw/analytics/interval.h>

List of all members.

Public Types
enum	Type { open, closed, openClosed, closedOpen }
Public Member Functions
	RWInterval ()
	RWInterval (T a, T b, Type t)
	RWInterval (const RWInterval< T > &i)
T	lowerBound () const
T	upperBound () const
Type	type () const
void	setBound (T x)
void	setBounds (T a, T b)
void	setType (Type t)
RWInterval< T > &	operator= (const RWInterval< T > &rhs)
bool	contains (T x)
Related Functions
(Note that these are not member functions.)
template<class T >
bool	operator== (const RWInterval< T > &lhs, const RWInterval< T > &rhs)

---

Detailed Description

template<class T>
class RWInterval< T >

RWInterval<T> is a general-purpose class for describing an interval of values. The values in the interval are of type T. An interval may be considered a set of contiguous values where the interval endpoints are either included or excluded from the set. If an interval's endpoints are excluded, it is said to be open; if the endpoints are included, the interval is said to be closed.

In Linear Algebra Module, the class RWInterval<T> is used to describe confidence intervals for regression predictions and parameter estimates.

Synopsis

 #include <rw/analytics/interval.h>

 RWInterval<double> ci( -1.031, 2.045, RWInterval<double>::closed);

Examples

The following example prints the linear regression prediction interval for the first pattern in the predictor matrix at a confidence level of 99 percent.

 #include <rw/analytics/linregress.h>
 #include <rw/analytics/interval.h>

 int main() {
  RWGenMat<double> predictorMatrix =
                   "5x2 [1.2 2.1 8 7 3 3.2 6.4 4.6 2 2.3]";
  RWMathVec<double> observationVector = "[2.5 3.7 1.4 2.3 5.6]";

  RWLinearRegression lr(predictorMatrix, observationVector);
  RWMathVec<double> firstPredPattern = predictorMatrix(0,RWAll);
  RWInterval<double> interval =
                   lr.predictionInterval(firstPredPattern, 0.01);

  cout << "Interval lower bound: " << interval.lowerBound() <<
          endl;
  cout << "Interval upper bound: " << interval.upperBound() <<
          endl;
  return 0;
 }

---

Member Enumeration Documentation

template<class T>

enum RWInterval::Type

If the left endpoint is a and the right endpoint is b, and

then the values of the Type enumeration have the following meanings:

Enumerator:

open	(a,b)
closed	[a,b]
openClosed	(a,b]
closedOpen	[a,b)

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Constructor & Destructor Documentation

template<class T>

RWInterval< T >::RWInterval

(

)

[inline]

Constructs an empty interval.

template<class T>

RWInterval< T >::RWInterval	(	T	a,
		T	b,
		Type	t
	)			[inline]

Constructs an interval of type t with endpoints a and b.

template<class T>

RWInterval< T >::RWInterval

(

const RWInterval< T > &

i

)

[inline]

Constructs a copy of i.

---

Member Function Documentation

template<class T>

bool RWInterval< T >::contains

(

T

x

)

[inline]

Returns true if the interval contains x, otherwise returns false.

template<class T>

T RWInterval< T >::lowerBound

(

)

const [inline]

Returns the interval's lower bound.

template<class T>

RWInterval<T>& RWInterval< T >::operator=

(

const RWInterval< T > &

rhs

)

[inline]

Sets self equal to rhs.

template<class T>

void RWInterval< T >::setBound

(

T

x

)

[inline]

Sets the interval's upper bound to x if x is greater than the current upper bound. Otherwise, sets the lower bound to x.

template<class T>

void RWInterval< T >::setBounds	(	T	a,
		T	b
	)			[inline]

Sets the interval's lower bound to the smaller of the two values and the upper bound to the larger of the two values.

template<class T>

void RWInterval< T >::setType

(

Type

t

)

[inline]

Sets the interval's type to t.

template<class T>

Type RWInterval< T >::type

(

)

const [inline]

Returns the interval's type.

template<class T>

T RWInterval< T >::upperBound

(

)

const [inline]

Returns the interval's upper bound.

---

Friends And Related Function Documentation

template<class T >

bool operator==	(	const RWInterval< T > &	lhs,
		const RWInterval< T > &	rhs
	)			[related]

Returns true if the intervals have the same endpoints and type.